The present disclosure relates to a bipolar junction transistor and a method of manufacturing the same, and more particularly, to a bipolar junction transistor (BJT) having a relatively reduced size and an improved current gain (hfe) and a method of manufacturing the same.
A bipolar junction transistor has a lower noise level than a Metal Oxide Semiconductor Field Effect Transistor (MOSFET). Further, the bipolar junction transistor shows a wide range of linear gain and has excellent frequency response characteristics and current driving capability.
The bipolar junction transistor includes an emitter, a base, and a collector, with device isolation regions being disposed between the emitter, the base, and the collector.
A conventional bipolar junction transistor of the prior art may include an emitter region that is formed within a substrate with ring-shaped base region surrounding the emitter region, and a ring-shaped collector region surrounding the base region. Further, a conventional bipolar junction transistor of the prior art may include a ring-shaped second base region surrounding the collector region, and the first base second base regions may be electrically connected by a deep well region.
A conventional bipolar junction transistor of the prior art may further include a ring-shaped second well region configured to surround the second base region, with a well contact region being disposed on the second well region. Further, the second well region and the well contact region may be used to apply a bias voltage to the substrate. Further, device isolation regions may be disposed between the emitter contact region, the collector contact region, the base contact region, and the well contact region.
A conventional bipolar junction transistor of the prior art may further include an insulating layer that is disposed on the substrate, with metal wiring disposed on the insulating layer to provide electrical connection to the emitter, collector, base, and well contact regions. The construction of the conventional bipolar junction transistor of the prior art is described in greater detail in the detailed description, below.
A conventional bipolar junction transistor array of the prior art may be formed by connecting a plurality of bipolar junction transistors with each other, thereby improving the current gain of the bipolar junction transistor array. However, a disadvantage of this technique of the prior art is that the size of the bipolar junction transistor array may be increased in proportion to the number of the bipolar junction transistors connected with each other. This technique has the disadvantage of requiring a greater physical size for the transistor array where it is otherwise desirable to minimize size.